Replace `is-set` with `instanceof Set`

[MichaelDeBoey]

npx github:Fuzzyma/e18e-tools is-set -n 100 -q -o md  -U https://npm.devminer.xyz/registry

#	Downloads	Traffic	Version	Package	PR	Notes
1	182.88M	1399.60 GB	^2.0.3	es-abstract
2	131.71M	1008.01 GB	^2.0.3	which-collection
3	39.45M	301.91 GB	^2.0.2	es-get-iterator
4	61.67k	472.00 MB	^2.0.3	set.prototype.difference
5	30.09k	230.26 MB	^2.0.3	set.prototype.intersection
6	27.17k	207.93 MB	^2.0.3	set.prototype.symmetricdifference
7	24.80k	189.83 MB	^2.0.3	set.prototype.union
8	10.22k	78.24 MB	^2.0.3	set.prototype.issubsetof
9	9.59k	73.39 MB	^2.0.3	set.prototype.issupersetof
10	9.04k	69.18 MB	^2.0.3	set.prototype.isdisjointfrom
11	3.17k	24.27 MB	^2.0.3	fca-smart-shankar

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Related: e18e/module-replacements#713